As the construction industry transitions to clean energy and low carbon construction methods, it is critical for all disciplines to be trained in how these systems work. The Passive House program is a critical component to bring low carbon construction to all project types, particularly as incentives and codes in Massachusetts advance towards Passive House levels. To ensure successful projects achieve full certification, it is critical to engage the PHIUS Verification team early in the design process to help provide a roadmap. Having a Verifier engaged early in the project is a way to capture all of the various requirements in a streamlined and meaningful way, and to help bring construction methods and training to the construction team. Working with an experienced verifier allows the training of on site personnel and identification of the issues to help with construction. The verification team will be present on site and working with the builder to ensure the project is built in a simple and repeatable way. Being able to verify the performance of the envelope by running whole building blower door testing is also critical to building envelope performance. As an experienced verifier in many green building programs, we will review our internal process as a verifier to provide streamlined feedback early in design, and our training and feedback process through construction. Having a systematic way to provide feedback for programs such as Passive House, Energy Star Multifamily, Indoor AirPLUS, DOE Net Zero Energy Ready, and various utility incentive programs is critical to ensure the project actually achieves the low-carbon goals.